Study On Water Saving Optimizing Irrigation Schedule Of Interplanted And Economic Crops In Hetao Irrigation District

During the Eleventh Five-years Plan, all these situations which facing to vigorously develop water-saving agriculture ,subustantially increaing in water use efficiency ,making great efforts to adjust agriculture planting structure,increasing the water-saving crops proportion, agriculture development requirement of improving farmers income and the actual situation of severe water shortage, make the workers aroused much more attention.This paper researched the non-sufficient irrigation schduule of wheat intercroping sunflower,wheat intercroping corn and tomato and preliminarily study the reasonable and efficient irrigation schedul based on the Zhifeng esperimental field in Hetao Irrigatin District of Inner Mongolia.By systemic theory analysis and research,some main conclusions were obtained as followings:(1)The actual evapotranspiration respectively was 508.29mm,513.86mm during the reproductive period in the years of 2008 and 2009.The water requirement discipline istiller～jointing>jointing～heading>heading～mature> seedling～tiller during the producttivity period of wheat intercroping sunflower. The appropriate crop～water model is Jensen model of wheat intercroping sunflower.The diversification discipline of sensitiv index to water at each growth stages of wheat intercroping sunflower isλ2>λ3>λ4>λ1. The irrigation frequency is 3 times during the growing set of wheat intercroping sunflower The appropriate scale irrigation is 60m3/mu and the water use efficiency respectively is 1.41kg/m3.The key water requirement period which the water requirement can reach up to 6.3mm/d in one day is symbiotic period of wheat intercroping sunflower.Weather the water reauirement can be satisfied will play an importment role in increasing crop yield .(2)The actual evapotranspiration respectively was 686.66mm,677.06mm during the reproductive period in the years of 2008 and 2009.The water requirement discipline is jointing～heading> tiller～jointing>trumpet～grouting> tasseling～grouting>seedling～tiller during the productivity period of wheat intercroping corn. The appropriate crop～water model is Jensen model of wheat intercroping corn and the diversification discipline of sensitiv index to water at each growth stages isλ3>λ2>λ5>λ4>λ1.The key water requirement period which the water requirement can reach up to 4.8mm/d is jointing–heading.The irrigation frequency is 5 times during the growing set of wheat intercroping corn.The appropriate scale irrigation is 60m3/mu and the water use efficiency respectively is1.63kg/m3 of wheat intercroping corn.Enough water resources can be used to make sure the nutrient transport during the critical formation period of maize grain in 8～9month.(3)The actual evapotranspiration respectively was 413.38mm,422.98mm during the reproductive period in the years of 2008 and 2009.Considering from unilateral water productivity of grain, The tomato's water use efficiency which changed form 25.00kg/m3 to 29.36kg/m3 is efficient.From the comparative analysis of border irrigation and furrow irrigation shows that:the furrow irrigation tomato which was irrigated in rapid growth stage and flowering stage can achieve ideal output(7780kg/mu) and high water production efficiency(29.36kg/m3)under the conditions that tomato use a smaller scale irrigation(22.5m3/mu)during the growing season. The ppropriate crop-water model is Blank model of tomato and the diversification discipline of sensitiv index to water at each growth stages is flowering and fruitage - flourishing fruitage period>seedling stage- flowering and fruitage>flourishing fruitage period -final phase of fruitage. (4)Form the optimization results obtained by the irrigation system showed that:the irrigation volume of growing stage separately is 250mm and 450mm of wheat intercroping sunflower and wheat intercroping corn. The appropriate irrigation volume of furrow irrigation tomato which should be irrigated two times is 60～70mm while the appropriate irrigation volume of borde irrigation tomato which should be irrigated only one time is 60mm during tomato growing stage.